The Yankees captain is hitting just .259 in 216 at-bats. He's got just a single homer and 12 RBI and manager Joe Girardi has had to answer way more questions about why the 39-year-old is still hitting in the lineup's No. 2 spot than he'd like.

So, what's the deal? Mike Petriello at Fan Graphs makes a pretty interesting case that Jeter can't handle fastballs thrown at the league average of 92 mph or above anymore.

Petrillo says Jeter is seeing more fastballs than just about anybody in the game because teams are recognizing he can't do much with them. That's because, Petrillo says, Jeter's bat has appeared to have slowed big-time.

From Petrillo's post:

Other than a mild increase in strikeouts, Jeter’s peripherals aren’t all that different than they were during his quality 2012. He’s not losing his plate discipline or popping up more or chasing pitches or missing pitches; some of those things are actually better this year. It’s just that he’s no longer able to do anything with the pitches he’s touching, especially the hard ones. That he’s on pace to do something done only one other time in the last 60 years — qualify for the batting title as a shortstop at age 40 or older, along with 2007′s Omar Vizquel — says a lot both about who he is and why so few other players ever get the opportunity to. Even the great Jeter can’t fight off the cold truth of age.

What do you think? Better yet, what have you seen? Is Jeter, at this stage of his career, incapable of handling the heat?